基于双剪统一强度理论的刚性结构物竖直土压力计算

Calculation of Vertical Earth Pressure of Rigidity Structures Based on Two Shear Unified Strength Theory

采用双剪统一强度理论,考虑中间主应力的影响,对沟内埋管的竖直土压力进行计算,得到了刚性结构物的竖直土压力的统一解。该统一解具有普遍性,既适用于拉压强度不同的材料,也适用于拉压强度相同的材料。计算结果表明,当拉压比一定时,随着填土厚度的加深,竖直土压力随着中间主应力系数的增大而减小,即沟壁向上的摩阻力对管顶上土压力的卸荷作用更加明显。应用双剪统一强度理论可以得出更符合土体性质的竖直土压力,可以更好地发挥材料的强度潜能,使其在工程应用中取得显著的经济效益。

Based on two shear unified strength theory,the vertical earth pressure for pipe groove was computed by considering the intermediate principal stress, and the unified solutions of vertical earth pressure of rigid structures were obtained. The unified solutions had the universality, which were either suitable to different materials of tension-compression strength, or suitable to same materials of tension-compression strength. The calculation results show that when tension-compression ratio is certain, with the filling thickness being deepening, the vertical earth pressure decreases with increasing of the intermediate principal stress coefficient, ie the effect of ditch wall friction of upward pressure on the pipe unloading is more obvious. The vertical earth pressure which is more suitable for soil properties is gained by using two shear unified strength theory, and brings the strength of materials into full play, as well as obtains the remarkable economic efficiency in the engineering applications.